This invention relates to metalloporphyrins useful as catalysts for the oxidation of alkanes, and more particularly to metalloporphyrins containing nitro groups on the porphyrin ring.
Nitro-substituted metalloporphyrins are known in the art. R. Bonnett et al, J. Chem. Soc., 30, 2791-2798 (1965) disclose a nickel complex of .alpha.-nitrooctaethylporphyrin, and also uncomplexed .alpha.,.beta.,.gamma.-trinitrooctaethylporphyrin. E. C. Johnson et al, Tetr. Lett. 26, 2197 (1976) disclose a magnesium complex of 5,10,15,20-tetranitrooctaethylporphine. L. C. Gong et al, Com. J. Chem., 63, 401-405 (1985), disclose zinc complexes of mono-, di-, tri- and tetra-nitrooctaethylporphyrins. J. E. Baldwin et al, Tetrahedron, 38, 685 (1982), disclose a zinc complex of dinitrotetraphenylporphine. M. Catalano et al, J. Chem, Soc. Chem. Commun., 1535-1536 (1984) disclose nickel, palladium, copper, cobalt, iron, magnesium and zinc complexes of betanitromesotetraarylporphyrins containing in some instances one and in some instances two nitro groups.
The complexes of the Bonnett, Johnson and Gong disclosures above have octaethyl groups at the .beta.-pyrrolic positions of the porphyrin ring and nitro groups at the meso positions of the ring. The complexes of the Baldwin and Catalano disclosures have aryl, e.g. phenyl, groups at the meso positions of the ring, and nitro groups at one or two .beta.-pyrrolic positions of the ring.
U.S. Pat. No. 5,077,394, issued Dec. 31, 1991 to D. H. Dolphin et al, from an application Ser. No. 455,663 filed Dec. 21, 1989 as a division of application Ser. No. 181,859, Apr. 15, 1988, U.S. Pat. No. 4,892,941, which was a continuation-in-part of Ser. No. 39,566, Apr. 17, 1987, abandoned, discloses tetraphenyl porphyrins which are beta-substituted by fluoro or chloro and bear electronegative substituents, for example nitro substituents, on the phenyl.